/*! Copyright (c) 2010 Brandon Aaron (http://brandonaaron.net)
 * Licensed under the MIT License (LICENSE.txt).
 *
 * Version 2.1.2
 */

(function ($) {

  $.fn.bgiframe = ($.browser.msie && /msie 6\.0/i.test(navigator.userAgent) ? function (s) {
    s = $.extend({
      top: 'auto', // auto == .currentStyle.borderTopWidth
      left: 'auto', // auto == .currentStyle.borderLeftWidth
      width: 'auto', // auto == offsetWidth
      height: 'auto', // auto == offsetHeight
      opacity: true,
      src: 'javascript:false;'
    }, s);
    var html = '<iframe class="bgiframe"frameborder="0"tabindex="-1"src="' + s.src + '"' +
      'style="display:block;position:absolute;z-index:-1;' +
      (s.opacity !== false ? 'filter:Alpha(Opacity=\'0\');' : '') +
      'top:' + (s.top == 'auto' ? 'expression(((parseInt(this.parentNode.currentStyle.borderTopWidth)||0)*-1)+\'px\')' : prop(s.top)) + ';' +
      'left:' + (s.left == 'auto' ? 'expression(((parseInt(this.parentNode.currentStyle.borderLeftWidth)||0)*-1)+\'px\')' : prop(s.left)) + ';' +
      'width:' + (s.width == 'auto' ? 'expression(this.parentNode.offsetWidth+\'px\')' : prop(s.width)) + ';' +
      'height:' + (s.height == 'auto' ? 'expression(this.parentNode.offsetHeight+\'px\')' : prop(s.height)) + ';' +
      '"/>';
    return this.each(function () {
      if ($(this).children('iframe.bgiframe').length === 0)
        this.insertBefore(document.createElement(html), this.firstChild);
    });
  } : function () {
    return this;
  });

// old alias
  $.fn.bgIframe = $.fn.bgiframe;

  function prop(n) {
    return n && n.constructor === Number ? n + 'px' : n;
  }

})(jQuery);